Definition

Food Poisoning is any illness resulting from the consumption of contaminated food. Food poisoning can affect a crew member's performance of his duties and, in severe cases, the poisoning can result in incapacitation

Food poisoning usually arises as a consequence of improper handling, preparation, or storage of food.

Crew incapacitation due to food allergy is covered by a separate article

Causes of Food Poisoning

Bacteria

Bacteria are a common cause of food poisoning. The most common foodborne bacterial pathogens, accounting for the majority of harmful infections, are:

• Campylobacter,
• Salmonella, and
• Escherichia coli.

Toxins from bacterial infections are delayed because the bacteria need time to multiply and symptoms are not usually seen until 12 - 72 hours or more after eating contaminated food.

Exotoxins

In addition to disease caused by direct bacterial infection, some foodborne illnesses are caused by exotoxins which are excreted as the bacterium grows. Exotoxins can produce illness even when the microbes that produced them have been killed. Symptoms typically appear after 24 hours depending on the amount of toxin ingested. Commonly encountered toxins include:

• Clostridium botulinum - the rare but potentially deadly disease botulism occurs when the anaerobic bacterium clostridium botulinum grows in improperly canned low-acid foods and produces botulin, a powerful paralytic toxin.
• Staphylococcus aureus produces a toxin that causes intense vomiting.

Mycotoxins

The term ‘mycotoxin’ is usually reserved for the toxic chemical products produced by fungi (mould). Health effects include death, identifiable diseases or health problems, weakened immune systems without specificity to a toxin, and as allergens or irritants. Mycotoxins can appear in the food chain as a result of fungal infection of crops, either by being eaten directly by humans or by being used as livestock feed. Mycotoxins greatly resist decomposition or being broken down in digestion, so they remain in the food chain in meat and dairy products.

Ingestion of misidentified mushrooms containing mycotoxins may result in hallucinations.

Viruses

Viral infections make up perhaps one third of cases of food poisoning in developed countries. In the US, more than 50% of cases are viral and noroviruses are the most common foodborne illness, causing 57% of outbreaks in 2004. Foodborne viral infection are usually of intermediate (1–3 days) incubation period, causing illnesses which are self-limited in otherwise healthy individuals, and are similar to the bacterial forms described above.

Parasites

Parasites may be present in food or in water. They range in size, from tiny single-celled organisms to worms (e.g. tapeworms) visible to the naked eye. The illnesses they can cause range from mild discomfort to debilitating illness and possibly death.

Natural Toxins

Several foods can naturally contain toxins, many of which are not produced by bacteria. Examples include red kidney beans (the toxins are destroyed by cooking) and shellfish, particularly bivalve molluscs (filter feeders) such as mussels, oysters and clams. Symptoms can appear 10 - 30 minutes after ingestion and include nausea, vomiting, diarrhoea, abdominal pain, dry mouth, confused or slurred speech, and loss of coordination. In more severe cases, neurological symptoms can take several hours or up to three days to develop. People poisoned with high doses of toxin, or those in high risk groups such as older people and those with pre-existing medical conditions, can die.

Incubation Period

The long incubation period of many foodborne illnesses tends to cause sufferers to attribute their symptoms to stomach flu.

If symptoms occur within 1–6 hours after eating the food, it suggests that it is caused by a bacterial or natural toxin, or a chemical, rather than live bacteria.

If symptoms occur very rapidly after eating food, i.e. within minutes, then the cause may be a food allergy rather than poisoning.

Threats

• Food Poisoning as a consequence of eating contaminated food or water before commencing duty.
• Food Poisoning as a consequence of eating contaminated food or water in-flight.

Effects

Effects of food poisoning may include:

• Nausea and vomiting;
• Cramping abdominal pains;
• Diarrhoea;
• Headache;
• Fever.

Severe cases may lead to:

• Shock;
• Hallucination;
• Collapse/unconsciousness.

Scenarios

• The crew eat together during their rest period. Several crew members experience stomach problems prior to reporting for duty. The Captain seeks medical advice from a doctor qualified in aviation medicine and, after discussion with the company, the flight is cancelled.
• During the flight, the Captain feels unwell and is forced to leave the flight deck for protracted periods of time. The Co-pilot, begins to experience similar symptoms and has difficulty performing routine actions. The crew initiate a diversion to the nearest suitable aerodrome.

Defences

• Good Health - The human body encounters potentially harmful bacteria and toxins on a continuous basis and the body's digestive and immune systems usually manage these without there being any adverse effects. However, people with pre-existing health problems, and those weak immune systems are more vulnerable.

• Food Hygiene - Observation of food safety principles reduces the likelihood of food poisoning:

1. Prevent contaminating food with pathogens spreading from people, pets, and pests;
2. Separate raw and cooked foods to prevent contaminating the cooked foods;
3. Cook foods for the appropriate length of time and at the appropriate temperature to kill pathogens;
4. Store food at the proper temperature;
5. Use safe water for cooking.

• Personal Hygiene - always wash hands before handling food.

Solutions

Crews often suffer from food poisoning when eating out while on a layover/night-stop away from home base:

• If in doubt about the hygiene of a cafe or restaurant, don't eat there.
• In a location where water is not drinkable, avoid salads, fruit, and ice.
• Always eat freshly cooked food.
• Ensure all meat and fish is completely cooked.
• Avoid shellfish.
• Pilots should eat different meals.

In Flight:

• Operating flight crew should eat different dishes when in-flight meals are served;
• Pilots at the controls should eat at different times - a separation of at least 30 minutes is advisable.

Treatment of Food Poisoning

1. Assist the casualty to lie down and rest in a comfortable position;
2. Encourage the casualty to drink plenty of fluids:
3. Supply sick bags and tissues;
4. Keep the casualty warm;
5. Encourage the casualty not to eat anything;
6. Offer the casualty Ant-Diarrhoel or re-hydration sachets (Dioralyte);
7. If the casualty gets into shock due to dehydration then treat for shock;
8. If the casualty becomes unconscious, follow guidelines for treating an unconscious casualty - seek medical advice and consider landing at nearest suitable aerodrome to get medical assistance.

Accidents & Incidents

Events on the SKYbrary Database which list Food Poisoning as a causal factor:

Related Articles

• Pilot Incapacitation
• Food Allergy
• Bio Hazards - Guidance for Cabin Crew

Further Reading

• CAP 757: Occupational Health and Safety on-board Aircraft - Guidance on Good Practice, 2012.
• UK CAA CAP 1703: Aircrew guide to gastroenteritis, August 2018